Medial orbital wall fracture with concomitant medial longitudinal fasciculus lesions

Abstract

Isolated orbital fractures are rare and may cause entrapment of intraocular muscles. The medial longitudinal fasciculus extending bilaterally through the brainstem establish connections between III, VI, VIII, and XIth cranial nerves. Lesions of these fasciculi may cause clinical findings similar to those seen in orbital fractures leading to muscle entrapment. A 9-year-old girl suffered a crush trauma. She had a limited inward gaze of left eye and complaints of diplopia. Findings were thought to be secondary to a left medial orbital wall fracture detected by cranial computed tomography, there was also entrapment of the medial rectus muscle. The patient was evaluated for the presence of any intracranial pathology as nystagmus developed. Antioedema therapy was initiated. Cranial magnetic resonance imaging revealed multiple millimeter-sized lesions at the medial longitudinal fasciculus MLF of the pons. There was a dramatic improvement in clinical findings on the 17th day of antioedema therapy; a diagnosis of internuclear ophthalmoplegia was made, and the operation was canceled. The authors emphasize that clinical findings due to orbital fractures may also be signs of a concomitant intracranial lesion, and that this possibility should be considered in differential diagnosis